In a conventional technique, for example, an autonomous driving support device disclosed in Patent Literature 1 sets an output section before a switching start point where switching from autonomous driving to manual driving is started. In the output section, an actual traveling output of a vehicle is gradually switched from a traveling output requested by autonomous driving to a traveling output requested by a driver. As a result, a traveling speed of the vehicle can be smoothly changed in the switching from autonomous driving to manual driving.
With the autonomous driving function as disclosed in Patent Literature 1, the vehicle can cruise at a relatively high speed or perform following traveling in a state close to a preceding vehicle. However, when a driving change to the driver is performed in a traveling state controlled by the autonomous driving function, the driver has to receive the driving operation in a high driving load state. As a result, even when the smooth switching as described above is performed, the driver is likely to feel anxiety about the reception of the driving operation from the autonomous driving function.